Device for removing dew from grass surface growth

ABSTRACT

An apparatus ( 1, 1′ ) for removal of dew from vegetation of grass surfaces, especially putting greens of golf courses, comprises 
         a number of rollers ( 2 ) that are grouped into at least two parallel rows (R, R′) of several rollers each, in which the longitudinal axles of the rollers of one row are aligned,    a bearing arrangement ( 3 - 6 ) for freely rotatable mounting of rollers ( 2 ) in the mentioned group, and        

     an operating device ( 7 - 14 ) articulated to it, by means of which the apparatus ( 1, 1′ ) can be pushed over the grass surface during rolling of the rollers ( 2 ) on the vegetation.

The invention concerns an apparatus for removal of dew from vegetation of grass surfaces, especially putting greens of golf courses.

The dew deposits that occur in the nighttime and morning hours pose a serious problem for sensitive grass surfaces, like putting greens with extremely short-cut vegetation. If the dewdrops on the ends of the blades of grass are not removed in a timely fashion before sunrise, they act as optical lenses that focus the sunbeams and allow the upper ends of the blades of grass to be scorched. The consequences are at least a nonuniform change in vegetation, if not even the occurrence of brown or burned spots in the grass surface.

For this reason, sensitive grass surfaces, like putting greens, the reinstallation of which would be quite costly, must be freed of dew daily in the early hours (so-called dew removal). For this purpose, a long, thin, fiberglass rod is now in use, which is passed over the grass surface by the greenskeeper, in order to shake off dewdrops from the vegetation, so that they can percolate into the ground.

The method is extremely time-consuming, and also inefficient, since the rod can only be moved irregularly and dew removal therefore does not occur uniformly. Adjustment of the rod movement to soil unevenness, as deliberately provided in putting greens (“cambering” of the greens), requires considerable skill and increases the hazard of nonuniform treatment. Frequent walking on the grass surface being treated cannot be avoided either.

The task of the invention is to eliminate the drawbacks just outlined and to devise an apparatus that permits rapid and uniform removal of dew from the vegetation of the grass surface with the greatest possible protection, especially in uneven grass surfaces.

This objective is achieved with a new apparatus for removal of dew from vegetation of grass surfaces, especially putting greens of golf courses, which is characterized according to the invention by

a number of rollers, which are grouped into at least two parallel rows of several rollers each, in which the longitudinal axles of the rollers of one row are aligned,

a bearing arrangement for freely rotatable mounting of the rollers in the mentioned group, and

an operating device articulated to it, by means of which the apparatus can be pushed over the grass surface during rolling of the rollers on the vegetation.

In this manner, an apparatus is devised for the first time, with which sensitive grass surface vegetation can be quickly, gently and uniformly freed of dew. The rollers, arranged freely rotatable in parallel rows, form a type of roller carpet, which, when pushed over the grass surface, merely rolls on the vegetation instead of sliding, so that the vegetation is protected as much as possible, whereas effective and uniform shaking off of dewdrops from the vegetation is simultaneously achieved. The row arrangement of the rollers permits a considerable working width and therefore rapid and uniform work. The operating device, designed for pushing, guarantees that the operating person (for example, a greenskeeper) walks only on an already treated area, which also contributes to protection of the vegetation. The articulated engagement of the operating device ensures that the roller carpet can always lie flat. In practical experiments, it has been shown that, with the apparatus according to the invention, the same grass surface can be subjected to dew removal about four to five times more quickly than with the known fiberglass rods.

A preferred variant of the invention is characterized by the fact that the bearing arrangement for each row has a flexible axle, onto which the rollers are threaded with lateral spacing. Because of this, a roller carpet, flexible in the transverse direction, is created, which can be optimally adjusted to ground unevenness of the grass surface in the transverse direction, so that even in uneven grass surfaces, uniform and mild treatment is achieved.

It is particularly advantageous when the axles are made of an elastic material, which facilitates handling of the device during transport, setup and removal from the grass surface. The axles are preferably made of stainless spring steel for long service life.

According to another preferred feature of the invention, the rollers of adjacent rows are offset relative to each other. Because of this, even more uniform treatment is achieved.

In another particularly advantageous variant, at least three parallel rows are provided that lie in a common plane, in which the bearing arrangement permits pivoting of at least one of the rows from the common plane. In the first place, a greater surface of the roller carpet can be achieved by this, so that the contact weight of the device per unit surface is reduced, which contributes to protection of the vegetation. On the other hand, a roller carpet, also flexible in the longitudinal direction (i.e., the pushing direction), is created by this, which can also be optimally adjusted to ground unevenness of the grass surface in the longitudinal direction, so that even with a large-surface device, uniform and gentle treatment of uneven grass surfaces can be achieved.

The bearing arrangement of the rollers can be arbitrary, as long as the mentioned freely rotatable row grouping is made possible. A variant, preferred because of its simple and modular manufacturing possibility, however, consists of the feature that during use of axles, on which the rollers are threaded, the bearing arrangement includes individual brackets that engage between the rollers and articulate the axles there.

The number, length and arrangement of brackets can be chosen according to the strength and flexibility requirements. In a first preferred variant, the brackets each connect two adjacent axles in articulated fashion, so that each axle can be pivoted parallel to the other one. This also offers the possibility of rolling up the entire device for transport and storage in the manner of a carpet. In an alternative variant, the brackets extend over more than two adjacent axles, in order to articulate adjacent groups of axles together in group fashion. This variant requires fewer separate brackets, which reduces manufacturing and assembly demands, but with somewhat more limited flexibility of the roller carpet in the longitudinal direction.

Another possibility for reducing the manufacturing and installation demands, without significantly compromising the strength and lifetime, preferably consists of the feature that in the region of engagement of the operating device, brackets are arranged between each roller and each axle of this region, whereas the brackets in other regions are less frequently positioned.

In each case, it is particularly favorable if the rollers are made of a water-repellant material, preferably plastic. This prevents swelling of the rollers during operation, reinforces their dew-removal effect, and also facilitates cleaning after use.

The rollers are preferably hollow elements, which reduces the weight of the device and protects the vegetation even better. In the preferred variant of rollers threaded onto axles, it is advantageously prescribed that each roller be shaped with a central sliding sleeve that is passed through by the axle, in which the sliding sleeve seals off the interior of the hollow element relative to the axle. Because of this, penetration of water into the interior of the roller via the axle entry gap is effectively prevented.

The operating device of the apparatus can be arbitrary, as long as it permits even pushing of the roller carpet over the vegetation. A particularly simple and easy to handle variant consists of the feature that the operating device includes two pushrods that are articulated on the bearing arrangement with lateral spacing from each other. The separate pushrods can each be grasped by hand and permit excellent steerability and maneuverability of the apparatus during pushing.

It is particularly favorable if the pushrods are connected retractably on the bearing arrangement. In this manner, they can be folded flat onto the roller carpet for transport or storage of the apparatus. The roller carpet can even be wound around the folded pushrods, so that a compact, rigid package is produced for transport and storage.

As an alternative or in addition, the pushrods can be removed by means of quick-release couplings, for example, for cleaning, storage or replacement.

Additional features and advantages of the invention are further explained below by means of application examples with reference to the drawings. In the drawings:

FIGS. 1-4 show a first variant of the apparatus in a top view, front view, side view and perspective view;

FIG. 5 shows a detailed cutout from the roller rows from FIG. 1;

FIG. 6 shows a detailed cutout of the pushrod linkage from FIG. 3;

FIG. 7 shows one of the rollers of the device of FIGS. 1-6 in a perspective, exploded view;

FIG. 8 shows a second variant of the apparatus in a top view.

The apparatus 1 depicted in FIGS. 1-7 has several long rows R arranged parallel to each other in on plane and short rows R′ lying in-between, in which adjacent rows R, R′ are of different length and the two outermost rows R have the greater length.

Each row R, R′ has several elongated rollers 2 arranged with lateral spacing from each other, which are threaded freely rotatable onto a thin, flexible axle 3 or 4, preferably made of an elastic material, preferably stainless spring steel, in which the longitudinal axles of the rollers 2 are aligned with axles 3, 4. The flexibility of axles 3, 4 during use of apparatus 1 permits adjustment of the rows R, R′ in their longitudinal direction to the terrain of the grass surface being subjected to dew removal.

The length of the long axle 3 is selectable and, in the depicted application example, lies in the range of 2-2.5 m. The maximum possible length of the axles is essentially dictated by the total weight of the apparatus 1 that still permits convenient and reliable handling of the apparatus 1.

The rollers 2 preferably consist of a water-repellant material, for example, plastic, in order to avoid swelling of rollers 2, and preferably have a smooth surface. The dimensions of rollers 2 are chosen so that they rotate smoothly during pushing of apparatus 1 over the grass surface being subjected to dew removal. In the depicted application example, rollers 2, for example, have a diameter of 35 mm and a length of 60 mm.

The rollers 2, in the context of the invention, can consist of solid material or be designed hollow in the interior with corresponding stiffening ribs. FIG. 7 shows an example of the later variant. Roller 2 is made here by injection molding as a hollow element from two halves 2′, 2″ and formed with a (also two-part) central sliding sleeve 15′, 15″, through which the axle 3 or 4 can pass. The sliding sleeve 15′, 15″ is centered in the hollow element interior of roller 2 via stiffening ribs 16.

The ends of the sliding sleeve 15′, 15″ are pulled beyond the ends of roller 2 to reinforce axial bearing, as shown at 17.

The two halves 2′, 2″ are welded to each other by ultrasound. The annular end surfaces 18′, 18″ and 19′, 19″ lying against each other during welding are folded in complementary fashion, in order to achieve perfect sealing, so that entry of water into the hollow element interior of roller 2 is prevented.

The rollers 2 lie in one plane, in which the rollers 2 of one row R are offset to the rollers 2 of the adjacent row R′ at the gap. FIGS. 5 and 6 show that the adjacent rows R, R′ are articulated to each other by brackets 5, angled in step-like fashion. The ends of brackets 5 are rotatable around axles 3, 4 and arranged with lateral clearance between the rollers 2, as well as on the outer end of the outermost roller 2 of one row. The brackets 5 preferably consist of plastic. The number of brackets 5 is selectable and is essentially determined by the requirements on stability of apparatus 1. In the application example of FIGS. 1-7, the maximum number is shown, in which each roller 2 is enclosed by brackets 5. On the end of each axle 3, 4, threading is provided to mount a closure joint 6, for example, a cap nut.

It is apparent that the axles 3, 4, brackets 5 and the closure joint 6 together form a bearing arrangement 3-6 for rollers 2. It is understood that any other type of bearing arrangement to mount rollers 2 could also be used, as long as it permits the depicted grouping of rollers in rows in the fashion of a roller carpet. For example, the axles 3, 4 could be omitted, if the rollers 2 are themselves equipped with axle stubs, which engage in bearing openings of a mount, or such a mount could be equipped with axle pins that engage in end holes of the rollers, or the rollers 2 could engage directly into each other by means of complementary shapes, etc.

Operating devices 7-14, which is now explained in detail, serves to push the apparatus 1 over the grass surface undergoing dew removal.

Operating devices 7-14 includes two long pushrods 7 that can be grasped with each hand of the operating person. The pushrods 7, on their lower end, each have a quick-release coupling 8 and a threaded reduction piece 9 and, on their upper end, a handle 10. The two pushrods 7 are arranged on a row R or R′, preferably situated in the front third, each symmetrically from the middle of the row with mutual spacing, which enables an operating person to easily push and maneuver the apparatus 1.

For mounting of pushrod 7 on row R or R′, the roller 2 present at this location is not used, but is replaced by a flat, trapezoidal mount 11 linked to freely rotate on axle 3 or 4, and whose dimensions correspond to the length of the replaced roller 2 in the region of axle 3, 4. The mount 11 is enclosed on its upper end by a fork mount 12, which is connected to rotate with mount 11 by means of a threaded joint. The threaded joint in the depicted practical example consists of a hex bolt 13 and a cap nut 14. The fork mount 12 is configured on its upper end, so that it fits into the quick-release coupling 8. The quick-release coupling 8 permits rapid removal of the pushrod 7, whereas the threaded reduction piece 9 permits use of pushrods in the standard variant.

FIG. 8 shows an alternative variant of the apparatus 1′. The apparatus 1′ is constructed the same as apparatus 1, with the exception that the number of required brackets 5 is reduced without significantly compromising the strength of the apparatus. For this purpose, in the region 20 of contact of the pushrod 7, brackets 5 are arranged between each roller 2 and each axle 3, 4 of this region 20, whereas the brackets 5 in all other regions 21 are positioned less frequently, for example, only between every second roller 2.

The method of operation of apparatus 1, 1′ is as follows.

The apparatus 1 is first spread out as much as possible outside of the grass surface to be treated and the pushrods 7 are folded up into the working position, in which the operating person is outside of the grass surface for dew removal. The operating person then pushes the apparatus 1 in strips over the grass surface to be treated and, in this manner, strips off the dew from the vegetation of the grass surface. By pushing the apparatus 1, the operating person always walks on the already treated grass surface. Because of the flexible thin axles 3, 4 of rows R, R′, the apparatus 1 adjusts to any unevenness in the grass surface to be treated, so that all rollers 2 of apparatus 1 lie uniformly on the vegetation of the grass surface and can always operate under the same conditions. After completion of work, the individual rows R, R′ of rollers 2 are rolled together from the outside and the pushrods 7 are retracted, during which rolling up of apparatus 1 is made possible by the articulated connection of rows R, R′. By rolling up, the apparatus 1 takes up only little space and can easily be transported. Before rolling up, the apparatus 1, if necessary, is cleaned of adhering dirt and blades of grass by means of a water jet.

It is understood that the depicted application example can be modified in different ways within the scope of the general concept of the invention, especially with respect to the configuration and dimensions of the brackets. For example, it is possible, by corresponding shaping of the brackets, to combine several rows in groups, so that every three adjacent rows R, R′ are rigidly connected to each other. Here the brackets extend over the rows that are originally connected to each other. In this practical example, the axles 3, 4 of rows R, R′ are mounted to rotate both in the ends and in the middle part of the brackets.

In the context of the invention, it is also possible to configure the brackets fork-like in which the two tines of the fork each enclose a roller. In this application example, several brackets in the form of a double-fork are used for rigid connection of three rows R, R′, in which the axles 3, 4 are mounted to rotate both in the ends and in the middle part of the brackets.

In addition, the brackets can be assembled from several individual parts in the context of the invention.

It is also possible, in the context of the invention, to adjust the configuration and dimensions of the axles and rollers to the terrain shape of the grass surface to be treated. In the presence of large roughnesses of the grass surfaces to be treated, for example, with strong waviness of the grass surface, shorter, more elastic flexible axles with shorter rollers are advantageous. 

1. An apparatus for removal of dew from vegetation of grass surfaces, especially putting greens of golf courses, comprising: a number of rollers that are grouped into at least two parallel rows of several rollers each, in which the longitudinal axles of the rollers of one row are aligned, a bearing arrangement for freely rotatable mounting of rollers in said group, and an operating device articulated to said bearing arrangement, by means of which said apparatus can be pushed over the grass surface during rolling of rollers on the vegetation.
 2. An apparatus according to claim 1, wherein the bearing arrangement for each row has a flexible axle, on which the rollers are threaded with lateral spacing.
 3. An apparatus according to claim 2, wherein the axles are made of an elastic material.
 4. An apparatus according to claim 1, wherein the rollers of adjacent rows are offset relative to each other.
 5. An apparatus according to claim 1, wherein at least three parallel rows are provided, which lie in a common plane, in which the bearing arrangement permits pivoting of at least one of the rows from the common plane.
 6. An apparatus according to claim 2, wherein the bearing arrangement includes individual brackets which engage between the rollers and articulate the axles there.
 7. An apparatus according to claim 6, wherein the brackets each join two adjacent axles together.
 8. An apparatus according to claim 6, wherein the brackets extend over more than two adjacent axles, in order to articulate adjacent groups of axles together in groups.
 9. An apparatus according to claim 6, wherein in the regions of engagement of the operating device, brackets are arranged between each roller and each axle of this region, whereas the brackets are positioned with less frequency in other regions.
 10. An apparatus according to claim 1, wherein the rollers are made of a water-repellant material.
 11. An apparatus according to claim 1, wherein the rollers are hollow elements.
 12. An apparatus according to claim 11, wherein each roller is formed with a central sliding sleeve, which is passed through by axles, in which the sliding sleeve seals off the interior of the hollow element relative to axles.
 13. An apparatus according to claim 1, wherein the operating device includes two pushrods that are articulated to the bearing arrangement with lateral spacing from each other.
 14. An apparatus according to claim 13, wherein the pushrods are mounted retractably on the bearing arrangement.
 15. An apparatus according to claim 13 wherein the pushrod can be removed by means of quick-release couplings. 